CVE-2009-0238: Microsoft Office Remote Code Execution

Added to the CISA Known Exploited Vulnerabilities catalog on 14 Apr 2026. Vendor: Microsoft. Product: Office.

Microsoft Office Excel contains a remote code execution vulnerability that could allow an attacker to take complete control of an affected system if a user opens a specially crafted Excel file that includes a malformed object.

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (due 28 Apr 2026)